Thread-controlling device for sewing-machines.



R. G. WOODWARD. THREAD CONTROLLING DEVICE FOR SEWING MACHINES. APPLICATION FILED APR. 9, 1903.

1,072,291 Patented Sept. 2, 1913.

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R. G. WOODWARD.

THREAD CONTROLLING DEVICE FOR SEWING MACHINES.

APPLICATION FILED APB.9, 1903. 1 972,291 Patented Sept. 2, 1918.

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UITD STATES FATE T carrot RUSSEL G. WOODWARI), OF WAUKEGAN, ILLINOIS, ASSIGNOR TO UNION SPECIAL SEWING MACHINE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

THREAD-CONTROLLING DEVICE FOR SEWING-MACHINES.

Specification of Letters Patent.

Application filed April 9, 1903.

Pa tented Sept. 2, 1913.

Serial No. 151,825.

ing and to the letters and figures of reference marked thereon.

My invention relates to an improvement in thread controlling devices for sewing machines and particularly to a pull off and take up device for the looper thread, on:

double chain stitch machines.

The object of the invention is to provide an improved thread controlling device and particularly an arrangement for giving and taking up slack, the slack occurring when the looper begins to move forward and the thread remaining slack until it reaches the end of its forward movement. The slack is taken up as the looper moves backward and the needle descends until it has entered the loop properly and then the slaec again occurs, while the looper is moving toward the extremity of its backward throw, while the needle is pulling up the previous stitch and allows the needle thread to have freedom in going up and at the same time allows the looper thread to be carried up to the goods freely, giving the upper thread full control over the lower thread.

This invention has been designed especially for use upon machines for making very fine stitches, such machine having a variable looper movement with a short throw, substantially as shown in the application filed by Lansing Onderdonk, November 9th, 1901, Serial No. 81,760 patented December 31st, 1907, No. 875,671. In making long stitches upon a machine of this character, a take up for the lower thread is not absolutely necessary, as the looper pulls off its own thread and takes up its own slack, but in some kinds of work, as for example, in the sewing of silk gloves, a very fine stitch must be made, and this in vontion is of particular value in machines of this character.

The invention consists in the various matters hereinafter described and referred to in the appended claims.

The invention is illustrated in tl aceo1npanying drawing, in which Figure 1 is a front ele'mtion, with the bed plate removed, of a sewing machine embodying the invention; Fig. 2 is a skeletonized view showing the relation of the parts when the needle is at its lowest point and the looper at the extremity of its backward stroke; Fig. 3 is a. view similar to Fig. 2 showing the relation of the parts with the looper moving backward and the needle moving down, when the take up is about to cast oil. the thread; Fig. 4- is a view similar to .i ig. 2 with the looper at the forward end of the stroke and the needle at its highest poiut; Fig. 5 is a detail sectional view of the take up and cast off mechanism, and Fig. (i is a sectional view on line (3-6 of Fig. 4.

In these drawings the machine shown is of the well known llnion Special single nee dle, double chain stitch type with the trimmer and having a looper with a variable movement imi iarted to it by connections between the end of the looper rod and the needle lever extension, whereby a short looper having a short throw may be used, substantially as is set forth in the application of ()nderdonk above referred to. i

A represents the bed of the machine, it the goose neck, (3 the head thereof, 1) the needle bar, a the needle, lil the looper rocker, I) the looper, l the looper rod, (1 the needle lever, II the trimmer. The looper rod F is attached to the crank pivoted to the short stud (Z on the machine frame. Pivoted to the crank is a link (1 pivoted to the lower end of the needle lover extension f. By this arrangement a quick movement into and out of the needle loop is given to the looper, and a short looper with a short throw may be used.

Attached to the standard of the machine is a bracket plate 1., cz'irrying on its outer end a casing 2, in which is suitably arranged a plate 3, carrying two arms 4t having eyelets and carrying also a cast off plate 5. This plate 8 has a screw threaded lug within the casing and a screw 6 acts to adjust the eyelet arms and cast off plate vertically.

Upon the driving shaft S near its rear end, is an eccentric 7 embraced by an arm 8 which, at its rear end, is slidably pivoted on the bracket 9 attached to the bed of the machine. This carries at its front end take up fingers 10, which oscillate in a plane between the eyelet arms t and upon either side the cast off plate 5 and have shoulders 11 engaging the thread which runs between the eyelet arms, carrying the thread upwardly and rearwardly, until the plate 5 operates to cast off the thread from the shoulders.

Thread guides 12, 12 are arranged upon the needle lever extension which act in the backward oscillation of said needle lever extension, while the needle is going down, to pull off thread from the spools through the tension 13. The stud 1 1 on the crank c, to which looper rod F is attached, has a grooved collar or washer 15 thereon, which acts as a guide for the thread which is led over it and under a wire 16 on the frame of the machine, to the eyelet arm 4.

The manner of threading the looper is as follows: The thread is led from the spool to the lower tension 18 on the front face of the overhanging frame, to the thread guides 12, on the lower end of the needle lever extension, over the ball joint collar or --washer 15, under the wire 16 to the eyes on the adjustable arms a on the right and left hand side of the take up and cast off, thence to the heel of the looper and to the eye thereof.

In operation the take up and pull off devices work as follows: Assuming the needle to be in its lowest position and about starting up to throw out a loop, the take up shoulders are not acting on the thread but are on their downward movement, but as the looper goes forward and the crank carrying the collar 15 over which the thread is guided, moves downwardly, it gives slack thread to the looper faster than the looper travels and consequently the thread is slack from the starting of the looper forward until it reaches the end of its forward movement, but by reason of the course the thread takes over said collar 15 and under the wire 16, the thread will not be entirely slack so as to sag, but at the limit of its forward movement, will become fully slack. Just as the needle moves down and the looper begins to move back, the take up shoulders engage the thread and take up the slack in order that the needle may enter the loop properly, holding the thread until the needle has gone into the loop, when the cast off acts and lets the thread become slack again. On the upward movement of the arm carrying the collar 15, the looper thread is taken up gradually, and thus takes the slack out of the looper thread which is given ver away from the looper will not disturb the thread between the swinging arm and the looper, for the reason that more or less friction is placed on the looper thread by the collar, the thread guide and the shoulders of the take-up, which prevents the drawing ofthe thread backward by this movement of the needle lever extension.

Another advantage of handling the thread in a slack condition, as set forth, is that it avoids the wear of the eyes in the looper, which is a rather serious objection. In the machines as usually constructed, when the looper thread is drawn taut and handled in this condition, the eyes of the looper wear through or form grooves in the ends of the eyes, which is apt to cause breakage of the thread if there is an uneven surface in said thread.

Having thus described my invention, what I claim and desire to secure by Letters Patent, is

1. In a sewing machine, stitch-forming mechanism including a needle and a looper cooperating therewith to form stitches, a device operating upon the looper thread and giving slack thereto as the looper .moves forward, and a second device operating upon the looper thread while the looper is moving backward to take up the slack in the looper thread and release the thread after the needle has entered the looper thread loop, said first named device operating to take up the looper thread afterit hasvbeen re leased by said second device.

2. In a sewing machine, stitch-forming mechanism including a needle, and a variably speeded looper cooperating therewith to form stitches, a controller for the lower thread comprising devices for giving slack thread to the looper as it moves forward, and a full slack thread when the looper is at the end of its forward movement, atakeup operating to take up the. slack thread while looper is moving backward and a castoff for casting said thread from the take-up after the needle has entered the looper loop, said controller operated to gradually take up the slack after the thread is cast off the take-up.

3. In a sewing machine, stitch forming mechanism including a needle, and a variably speeded looper cooperating therewith to form stitches, a controlling device for the I lower thread, comprising a take up member to engage the thread and take up the slack on the backward movement of the looper, a cast off cooper. ting therewith and operating to give a slack thread after the needle has entered the loo'per loop, and devices for controlling the slack while the looper is completing its backward movement; substantially as described.

4:. In a sewing machine, stitch forming mechanism, including a needle, a variably spceded looper cooperating therewith to form stitches, a controlling device for the looper thread comprising a take-up member to engage the thread and take up the slack,

a castotl' cooperating therewith and operating to give slack thread to the looper after he needle has entered the looper thread loop, means for controlling the slack in the loopcr thread after it has been released by the cast-oil, including a thread engaging device and a thread eye, and movable thread guides through which the thread passes from the supply to the slack thread controller and take-up member.

5. In a sewing machine, stitch forming mechai'iism including a needle, and a looper cooperating therewith to form stitches, stationary guides for the thread, take up member reciprocating in a plane between the guides and operating in one movement of the looper, a cast off plate cooperating with said take up member, a slack controlling device operating upon the thread and comprising a swinging arm over which the thread is guided to give slack as the looper moves forward and gradually take up the slack in the reverse movement, and a stationary guiding wire under which the thread is guided, and a pull oft; substantially as described.

6. In a sewing machine, stitch forming mechanism including a needle, and a looper cooperating therewith to form stitches, stationary guides for the thread, take up member reciprocating in a plane between the guides and operating in one movement of the looper, a cast off plate cooperating with said take up member, a slack controlling device operating upon the thread and con'lprising a swinging arm over which the thread is guided, and a stationary guiding wire under which the thread is guided, and a pull ott' carried .iy the needle lever, and connections between the needle lever and the swinging arm, whereby the latter is operated; substantially as described.

7. In a sewing machine, stitch torn'iing nnazlninisn'i including a needle and a looper cooperating therewith to form stitches, a thread controller, comprising devices for ving slack thread to the looper faster than the looper travels in its forward movement, giving a full slack thread when the looper is at the end of its forward movement, a take up, timed to take up the slack when the looper begins to recede and to hold it tautuntil the needle has entered the loop,

a :ast o'tl' for giving slack after the needle has entered the loop and devices for gradually taking up the slack while the looper is passing to its extreme backward position; substantially as described.

8. in a take-up device oil the character described, stationary guiding arms for the thread carried on a suitable support, a castoll' plate also carried by said support, and means for adjusting said plate and guiding arms simultaneously; and a thread-controlling device arranged to cooperate with the guiding arms and cast oll' plate substantially as described.

5). In a sewing machine, stitch-:lorming mechanism iiicluding a needle, a looper 00- operating therewith to form stitches, a mov able member, slack-controlling devices including a swinging arm over which the thread is guided, a stationary guiding wire under which said thread is guided, thread guides carried by the movable member, and connections between the latter and the swinging arm, said stationary guiding wire being so disposed relative to said swinging arm that slack thread is given up during the entire Forward movement of the looper.

1.0. In a sewing machine stitch-:lorming mechanism including a needle, a looper eome1ating therewith to form stitches, slackcontrolling devices including a swinging arm over which the thread is guided, a stationary thread guide through which said thread is guided on its way to the looper from said swinging arm, and means for operating said swinging arm, said stationary guide being so disposed relative to said swinging arm that slack thread is given up during the entire forward movement of the looper, and a take-up and castolt' mechanism for engaging the looper thread be tween the swinging arm and the looper.

11. In a sewing machine, the combination of a stitch-forming mechanism including a needle and a looper, a needle lever, a needle lever extension carried thereby, a thread guide located on said needle lever extension, a swinging arm opcratively connected with the needle lever extension and moved thereby, a guiding device carried by said arm over which the thread is guided from the needle lever extension to the looper, and a statioimry thread guide secured to the stationary part of the machine :irame between the swinging arm and the looper and under which the thread is guided.

12. In a sewing machine, stitch-forming mechanism including a needle and a. looper cooperating therewith to form stitches, a needle lever having an extension, a thread guide located on the needle lever extension, a swinging arm operatively connected with the needle lever extension, and provided with a guiding device over which the thread is guided, a thread guide secured to a stationary part of the machine frame, andunder which the thread is guided, and a take-up and cast-oif mechanism; substantially as described.

5 13. In a take-up device of the character described, stationary guiding arms for the thread carried on a suitable support, a castofi plate also carried by said support, means for adjusting said plate and guiding arms simultaneously and a take-up member 00- 10 operating therewith; substantially as described. o

In testimony whereof I aflix my signature, in presence of two Witnesses.

RUSSEL G. VVOODWARD. Witnesses:

CHESTER MONEIL,

CHARLES E. JOHNSON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

